[Objective] To resolve the ambiguities of HLA genotyping generated by next generation sequencing (NGS) using nanopore sequencing technology. [Methods] A total of 38 samples with ambiguous HLA genotyping by NGS in our laboratory were collected, and HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, -DPA1 and -DPB1 loci in these samples were amplified using primers in the same commercial NGS HLA genotyping kit, then subjected to third-generation library construction, and sequenced on the nanopore sequencer. The sequencing data were converted into Fastq files and analyzed by software, and the genotypes of 11 HLA loci were obtained. The ambiguities were counted directly. [Results] The high-resolution genotyping at the second domain of 11 HLA loci of 38 samples using the third generation sequencing (TGS) were consistent with the results of the NGS method at a rate of 100%. The genotypes for the HLA-A, -B, -C, -DRB3, -DRB4, -DQA1 and -DPA1 loci by TGS were all only one result, and the discrimination rate for ambiguities of the HLA-A, -B, -C, and -DQA1 loci (all caused by the difficulty in phasing due to the short NGS read length) was 100%. Among the HLA-DRB1, -DRB5, -DQB1 and -DPB1 loci, the discrimination rate of TGS for the ambiguities caused by non-amplification of exon 1 was 0% and by the short NGS read length was 100%. [Conclusion] Nanopore technology was used to identify the ambiguities of 11 HLA loci in this study, and the ambiguities caused by the short read length disadvantage of the NGS method could be solved effectively and the accuracy of HLA genotyping would be improved.

Neurofibromatosis type 1（NF1）is one of the most common autosomal dominant disorders. The disease is caused by mutations in the NF1 gene，which can involve multiple systems and have a variety of clinical manifestations，including café au lait macules，lisch nodules，neuroglioma，autism spectrum disorder，learning difficulties，neurofibromas，and skeletal dysplasia，et al.In previous studies on the pathogenesis of NF1，most of them have focused on the regulation of the RAS signaling pathway by neurofibromin. In recent years，researchers start exploring pathways other than RAS signaling to explore the potential functions of neurofibromin. This article reviews the research progress on the pathogenesis of NF1 in recent years，aiming to provide new ideas for treatment.

Objective:To assess the value of combined chromosomal karyotyping and chromosomal microarray analysis (CMA) and/or copy number variation sequencing (CNV-seq) for the prenatal diagnosis for women with advanced maternal ages, and to explore the challenges of prenatal genetic counseling brought by the types of fetal CNVs and uncertainty of related phenotypes.Methods:A retrospective analysis was carried out on 1 841 women with advanced maternal age who underwent interventional prenatal diagnosis at the Prenatal Diagnosis Center of Xiamen University Affiliated Women and Children′s Hospital from January 2017 to December 2020. Routine chromosomal karyotyping analysis and CMA/CNV-seq detection were carried out.Results:CMA/CNV-seq had detected pathogenic variants in 2 cases which had failed karyotyping analysis. Two hundred and twenty one fetal chromosomal abnormalities were detected by karyotyping analysis, among which 187 were detected by CMA/CNV-seq. CMA/CNV-seq analysis of 23 cases with balanced chromosome structural aberrations and 10 cases with low proportion mosaicisms (including a marker chromosome) had yielded a negative result. In addition, 26 cases (26/1 841, 1.4%) with pathogenic CNVs were discovered among those with a normal karyotype, of which 13 (50.0%) were recurrent CNVs associated with neurocognitive impairment, with 22q11.21 microdeletions and microduplications being the most common types (26.92%).Conclusion:The combination of karyotyping analysis and CMA/CNV-seq not only increased the rate of prenatal diagnosis, but also complemented with each other, which has facilitated genetic counseling and formulation of prenatal diagnosis strategy for the affected families.

Objective:To analyze the sequence of a novel HLA- DPB1 allele in an individual. Methods:A individual identified from the database of blood donors for matched platelet transfusion at the Blood Center of Zhejiang Province in May 2022 was selected as the study subject. HLA genotype of the individual was determined by next-generation sequencing (NGS) on an Ion Torrent S5 platform. The sequence of the HLA- DPB1 locus was also determined by NGS on an Illumina Miseq platform and third generation sequencing using Oxford Nanopore MinION. This study was approved by Medical Ethics Committee of the Blood Center of Zhejiang Province (Ethics No. 2021-001). Results:A novel HLA- DPB1*02 allele was identified in the specimen, for which the closest genotype was HLA- DPB1*02: new, 17: 01: 01G, with the variant located in exon 3. Meanwhile, the NGS also revealed a novel HLA- DPB1*17 allele, with the closest genotype being HLA- DPB1*02: 01: 02G, 17: new. Both the HLA- DPB1*17: 01: 01: 01 and novel HLA- DPB1*02 alleles were identified by third-generation sequencing. Compared with the HLA- DPB1*02: 01: 02: 01 allele, the novel allele had a G>A variation at position 369 in the exon 3, which did not result in amino acid change. Conclusion:A novel HLA- DPB1 allele has been identified and validated by both NGS and TGS, which has been named as HLA- DPB1*02: 01: 69 by the World Health Organization Committee on Nomenclature of Factors of the HLA System.

Objective:To develop a tetramer probe targeting fibroblast activation protein (FAP), named 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA)-4P(FAP inhibitor (FAPI)) 4, evaluate its biodistribution and PET image in FAP-positive-tumor bearing nude mice, and explore its feasibility as a novel radio-regent for treatment of FAP-positive tumor. Methods:FAP tetramer probe was constructed on the FAPI-46 motif with four mini-polyethylene glycol (PEG)(PEG 3) spacers between the four FAPI motifs, denoted as 4P(FAPI) 4. DOTA was used as the chelator for radiolabeling with 68Ga and 177Lu. The FAP binding characteristics were test by in vitro cell competitive binding experiment. Small-animal PET, in vivo biodistribution, and radionuclide targeting therapy were performed in HT-1080-FAP tumor bearing nude mice ( n=39). Independent-sample t test was performed to analyze tumor uptake data, and two-factor repeated measures analysis of variance was utilized to compare tumor volume data in radioactive isotope therapy. Results:Cell experiment showed that FAPI-tetramer and FAPI-monomer had similar half maximal inhibitory concentration values (3.29 and 2.15 nmol/L). 68Ga/ 177Lu radiolabeled FAPI-tetramer had better tumor uptake and retention than FAPI-monomer in small-animal PET and in vivo biodistribution experiment, with the tumor uptake for 177Lu-DOTA-4P(FAPI) 4 and 177Lu-FAPI-46 at 48 h of (18.72±1.32) vs (2.72±1.20) percentage activity of injection dose per gram of tissue (%ID/g) ( t=15.55, P<0.001). 177Lu-DOTA-4P(FAPI) 4 group showed best anti-tumor efficacy compared with 177Lu-FAPI-46 and control group in radionuclide targeting therapy. On the 2nd day after the start of treatment, the tumor volume in the tetramer treatment group was significantly smaller than that in the control group (mean difference 67.19 mm 3, P=0.049); on the 14th day after the start of treatment, the tumor volume in the tetramer treatment group was significantly smaller than that in the monomer treatment group (mean difference 414.33 mm 3, P=0.005). Conclusion:FAPI-tetramer can improve tumor uptake and retention ability compared with FAPI-46, and 177Lu-DOTA-4P(FAPI) 4 can be a promising radio-agent for FAP-positive tumor therapy.

Objective:To formulate surgical strategies and guide the implementation of laparoscopic anatomical hepatectomy with preoperative simulative resection.Methods:Twenty-two cases of hepatocellular carcinoma undergoing laparoscopic lobe, segment, subsegment and combined segment liver resection following preoperative simulative resection from Sep 2020 to Jan 2022 were enrolled in this study retrospectively.We observed and analyzed the operation time,intraoperative blood loss,postoperative hospital stay and postoperative complication.Results:All patients underwent laparoscopic hepatectomy successfully according to the preoperative simulative resection plan without conversion, some of them adjusted plan according to preoperative simulative resection. The median operation time was 170.0 min, the median intraoperative blood loss was 150.0 ml, the median times of pringle maneuver was done on 4 episodes, and the median postoperative hospital stay was 6.5 days. There were no severe postoperative complications in all cases.Conclusion:Preoperative simulative resection can plan the range of surgical resection accurately by visualizing important anatomical structures,greatly helping the actual surgical hepatectomy.

OBJECTIVE: To detect loss of heterozygosity (LOH) at human leukocyte antigen (HLA) loci in a Chinese patient with leukemia after haploidentical hematopoietic stem cell transplantation. METHODS: HLA genotyping was carried out on peripheral blood, hair follicle and buccal swab samples derived from the patient after the transplantation as well as peripheral blood samples from his parents by using PCR-sequence specific oligonucleotide probe method and PCR-sequence based typing method. Short tandem repeat (STR) loci were detected by using a 23 site STR assay kit and a self-developed 6 STR loci assay for the HLA regions. RESULTS: After the transplantation, the HLA genotype of the peripheral blood sample of the patient was identical to his father. The patient was HLA-A*02:01,24:02, C*03:03,03:04, B*13:01,15:01, DRB1*08:03,12:02, DQB1*03:01,06:01 for his hair follicle specimen. However, homozygosity of the HLA loci was found in his buccal swab sample. Only the HLA-A*24:02-C*03:03-B*15:01-DRB1*08:03-DQB1*06:01 haplotype from his father's was present, while the HLA-A*02:01-C*03:04-B*13:01-DRB1*12:02-DQB1*03:01 haplotype from his mother was lost. After the transplantation, the alleles of the 23 STR sites in the patient's peripheral blood sample were consistent to his father, with no allelic loss detected in his buccal swab sample. However, at least 4 STR loci in the HLA region were lost in his buccal swab sample. CONCLUSION LOH at the HLA loci has been detected in the buccal swab sample of a patient with leukemia who received haploidentical hematopoietic stem cell transplantation.
HLA Antigens/genetics* ; HLA-A Antigens/genetics* ; Histocompatibility Antigens Class I/genetics* ; Humans ; Leukemia/genetics* ; Loss of Heterozygosity

Circular RNA (circRNA) is a kind of RNA with a circular structure. The unique structure of circRNA endows it with various cell biological functions and characteristics. It has become a research hotspot recently. CircRNA can play a role via mechanisms, such as microRNA (miRNA) sponge, RNA binding protein, peptide translation and regulation of gene transcription. CircRNA was found to be associated with disc degeneration, spinal cord injury, scoliosis, and facet arthritis. Some techniques, including bioinformatics and molecular biology techniques, microarray and high-throughput sequencing, can be used to predict and to discover disease-related circRNA, aiming to evaluate whether circRNA can be used as a molecular biomarker for spinal and spinal cord diseases. Based on the current role of circRNA, the corresponding therapeutic strategies have been carried out in experimental animals, which can provide theoretical basis for gene therapy. At present, the researches in circRNA for spinal and spinal cord diseases are still insufficient compared with those in other fields. Currently, the main direction focuses on the miRNA sponge mechanism of circRNA. Due to the variety of diseases in spinal surgery, the research progress of circRNA is also varied. In addition, the development of microarray and high-throughput sequencing technology have greatly promoted the researches in circRNA. The availability of public database is of great significance in the study. The present review summarized the current researches status of circRNA in spinal and spinal cord diseases, aiming to deepen understanding of circRNA in spinal and spinal cord diseases.

Objective To analyze the clinical characteristics and risk factors for post-traumatic seizures (PTS) in children,so as to provide a theoretical evidence for clinicians to prevent PTS.Methods From January 2010 to November 2016,the clinical data and auxiliary examination of 388 post-traumatic patients hospitalized at the First Affiliated Hospital of Zhengzhou University were analyzed retrospectively.According to the presence of epileptic seizure,these patients were divided into PTS group and non post-traumatic seizures (nPTS)group.The risk factors associated PTS were investigated by univariate analysis.Results Among the 388 post-traumatic children,72 cases had seizures,which occurred almost predominantly less than 1 year.Fifty-six point nine percent (41/72 cases) were immediately PTS,and 31.9％ (23/72 cases) were early PTS,and 11.1％ (8/72 cases) were late PTS.Among the seizures types,generalized seizures accounted for 51.4％ (37/72 cases),and tonic-clonic seizures were in common;focal seizures accounted for 36.1％ (26/72 cases);focal combined generalized seizures accounted for 2.8％ (2/72 cases),and the remaining 9.7％ (7/72 cases) were ominous.Electroencephalogram showed the slow wave and spike wave most common.There were significant differences in factors statistically,included age,Glasgow Coma Scale (GCS) score,the severity of traumatic brain injury,cerebral contusion,subdural hematoma,therapy method between the patients with seizures group and the patients without seizures group (Z =4.717,x2 =13.079,17.852,5.664,17.457,5.496,all P ＜ 0.05).In single factor analysis and multi-factor regression analysis,age,GCS score,the severity of traumatic brain injury,subdural hematoma,therapy method were associated with the incidence of PTS (all P ＜ 0.05).Conclusions PTS is a severe complication of brain trauma in children.Small age,GCS ≤8 scores,severe brain injury,subdural hematoma,surgery are the risk factors of PTS.